Discrepancy between phone and booster

Brand new Koodo user here. My phone (Asus Zenfone 2) has been active for only a couple days, and data has been turned off until today. Today I turned on data and was out of my home wifi for a couple of hours. Most apps are prevented from using cellular data with the built in Asus firewall - I only allow Hangouts, WhatsApp/GCM and Outlook.

According to Self-Serve, I've used 5.654 MB of the data booster. According to my phone I've used only 395 KB. For this case, the discrepancy is a multiplication factor of approximately 15 - which doesn't make sense at all to me. With my previous provider (Petro-Canada Mobility), the phone's data count and the reduction in the balance approximately matched. On average I'd use 40-50MB a month (which with PCM reduced the prepaid balance by $4~5). I understand that Koodo rounds data sessions to the nearest 10KB, so there will likely be some discrepancy - but what defines a session? It seems like every 700 bytes my phone sends out is counted as a session of 10KB.

Searching found a couple similar posts from a few years back - but in those cases the discrepancy was a much lower multiplication factor and much higher data use (e.g. phone counted 3GB, Koodo 5GB).

Does anyone else have such huge discrepancy between their phone data counter and the Koodo data counter? Can anything be done about this? Is it just a "first initialization" thing, or will it continue. I've shut off data until I can figure this out.

Also, according to Self-Serve, I've used 7 minutes of the talk booster.According to my phone I received one call of 0:26 min, missed one call and received a second call of 5:00 minAccording to usage history, there was one incoming call of 0:47, and one incoming call of 5:30 that correspond to the calls I received. There is also a third "outgoing" call of 0:10 - this I assume is the call that got sent to voicemail (no message was left).I can understand the time discrepancy between my phone and Koodo (call time vs network connected time) - and I think the 7 minutes deducted are 1 + 6 for the two incoming calls.

Are calls that get sent to voicemail charged minutes if no message is left?Are calls that get sent to voicemail charged minutes if a message is left?

After a week of vacation overseas, with the phone not connected to Koodo at all, I can answer some of my own questions.

1) The data used on Self-Serve gas auto-magically corrected itself to show 0.371 MB of use. This equals 380 kB, which more or less matches the 395 kB reported by the phone. I'll re-enable the cellular data and monitor, however some previous posts alluded to Koodo "reserving" usage in advance, so maybe that explains the earlier discrepancy.

2) Calls that bounce to voicemail do not get charged minutes, whether or not a message is left. These calls are logged in the history as outgoing calls from phone to voicemail from location "All". Calling voicemail to retrieve messages does use minutes, and is logged in the history from phone to voicemail from my current location "MONTREAL QC". Other than the location, there seems to be no way to distinguish calls redirected to voicemail from message retrieval calls.